The Weapon Target Assignment (WTA) problem is the problem of assigning weapons to threats with the objective of minimizing the expected survival value of threats. On a real battlefield, the problem must be solved in quite short time, i.e., real-time. Considering combinatorial complexity of the problem and the strict time constraint, a fuzzy decision maker (FDM) is proposed as an alternative in helping commanders to decide on proper WTA. The idea is to build a FDM for a given data set using an extended grid partitioning based on sensitivity analysis of the input variables. The proposed decision maker is implemented and then tested with a number of randomly sampled WTA instances on realistic scenarios. The proposed system has a satisfactory performance. © 2011 IFAC.